mazaruni, Rivulus Myers [G. S.] 1924:1 [American Museum Novitates No. 129; ref. 15457] Mutusi Hole, Mazaruni River, Guyana. Holotype: AMNH 8346. Paratypes: AMNH 8347 (5). •Status uncertain -- (Huber 1992:314 [ref. 20639]). •Valid as Rivulus mazaruni Myers 1924 -- (Lazara 2001:280 [ref. 25711], Costa in Reis et al. 2003:538 [ref. 27061], Costa 2006:139 [ref. 28875] in subgenus Cynodonichthys, Costa 2010:84 [ref. 30788], Vermeulen 2022:15 [ref. 39817]). •Valid as Anablepsoides mazaruni (Myers 1924) -- (Costa 2011:243 [ref. 31655], Costa et al. 2013:292 [ref. 33108], Nielsen 2016:166 [ref. 34861], Taphorn et al. 2022:36 [ref. 41297]). Current status: Valid as Anablepsoides mazaruni (Myers 1924). Rivulidae: Rivulinae. Distribution: South America: Essequibo River basin (Guyana) endemic. Habitat: freshwater.